Facile synthesis of low-cost chitosan/Fe3O4@C composite for highly efficient adsorption of levofloxacin antibiotic

Abstract

Developing a highly efficient and cost-effective adsorbent material for the removal of antibiotics in wastewater has received great attention over the recent years. In this work, we developed a novel magnetic hybrid composite adsorbent using low-cost starting materials. First, rice husk was carbonized to obtain carbon materials (C), which were then used as a host for carrying ferrite Fe3O4 nanoparticles, namely Fe3O4@C. Then, chitosan was deposited onto the Fe3O4@C by co-precipitation method to obtain a hybrid composite of chitosan/Fe3O4@C (CS/Fe3O4@C). The chitosan/Fe3O4@C composites produced with varying compositions were applied for the removal of levofloxacin antibiotic in an aqueous solution. The effects of the experimental conditions, including the composite composition, pH media, concentration, and adsorbent amount were systematically investigated. The results indicated that the composites’ compositions strongly affected their removal efficiencies toward levofloxacin. The highest removal efficiency of ∼90% for levofloxacin achieved with the use of the CS/Fe3O4@C-0.5 adsorbent, surpassing the pristine carbon and Fe3O4@C. The prepared CS/Fe3O4@C exhibited a good reusability after several recycles. Moreover, the CS/Fe3O4@C adsorbent was effectively recovered after use by applying an external field. The study provides a facile approach to prepare a low-cost and highly efficient adsorbent material for wastewater treatment.